| Subject | Re: SLOW OPENING MDX FILE |
| From | Ed furche <Ed@univ-computers.com> |
| Date | Fri, 23 Feb 2018 12:52:13 -0500 |
| Newsgroups | dbase.getting-started |
Mervyn Bick Wrote: > On 2018-02-23 3:17 PM, Ed Furche wrote: > > > Sorry about the caps. I have been chastised before about this. > > Answers: > > I haven't packed in a while. > > See the mdx's below: > > Production MDX file: WO.MDX > ......I already have a program that will buil MDX from scratch.. I will get rid of all trims. I didn't know about using the - rather than plus. Thank you for the in-depth explanation. > > Index TAG: WO Key: WONO...... > > Index TAG: WONAME Key: RTRIM(TECH)+WONO > > Index TAG: WOOPENTECH Key: OPEN+RTRIM(TECH) > ...... > > Index TAG: WOOPENNAME Key: OPEN+RTRIM(TECH)+CUSTNAME1 > > > > > i am trying to use the WO mdx whjich is on one field only (9 chars). > > Windows 7 dbase 2.8 16000 recs > > If i just go to command prompt and say: > > Use WO > > Set order to WO > > The prompt comes back immediately. > > It is just in this one WFM that it is slow. I ran a debug > > and it literally stops for 15-20 seconds when i address the WO MDX. > > > Using RTRIM() or LTRIM() in an index expression is an absolute NO-NO. > > All the entries in the index must be the same length otherwise there is > a very real danger of corrupting the index. I wouldn't expect the > WONAME index to upset the WO index but as they both use the WONO field > it is not beyond the bounds of possibility. Mysterious things happen > when you get into the BDE. :-) > > If you are using the indexes only to order the rowsets simply get rid of > the RTRIM() functions. The rows will still be in the same order. > > If you are using the indexes to implement SEEKs then use - instead of + > to link the fields. Using - moves all trailing spaces to the righthand > end of the index expression. Your existing search strings should, > therefore, still work provided OPEN is a single Y/N character. If OPEN > is more than a single character I'm afraid you're going to have to find > all your SEEKs and fix the search strings. > > For the WOOPENTECH index simply removing the RTRIM() should do the trick. > > Rather than simply changing the index expression it would probably be > better to delete the .mdx file and rebuild it from scratch. > > First off, backup both the .dbf amd .mdx files and the .dbt file if > there is a memo field in your table. > > If you don't have a program which creates your indexes from scratch (i.e > rather than just reindexing) then you need to build one. In the Command > Panel run the following command > > do :duflp:cretable7 with 'wo.dbf' > > This will create a file cretable.txt Open this in the sourcecode > editor and get rid of the code which creates the table. Not strictly > necessary as the code won't run if the table exists but it's just > cluttering up the file so delete it anyway. > > Fix the dodgy index expressions and use "Save As" to save the code as a > .prg file. > > > Delete wo.mdx As the index files don't show in the Navigator use the > underlying operating system command in the Command Panel !del wo.mdx > (This is much quicker than using the Windows File Explorer. :-) ) > > Open wo.dbf. dBASE will complain that the .mdx is missing. Select > "Open and Detach" from the options. Close the table and run the > indexing program. > > If the problem persists after all that I really don't know what else you > can try. > > Mervyn. > > > > > > > > > > > > > > > > > > > > > > > | |